Epileptic and nonepileptic paroxysmal events out of sleep in children.

The distinction between epileptic and nonepileptic events out of sleep may represent a significant challenge to the pediatrician. It is known that sleep can facilitate epileptic activity and that seizures in sleep tend to occur during specific sleep stages. Certain epilepsy syndromes have a well-documented and strong association with sleep and these can present with a variety of bizarre behaviors and motor activity. Disorders that may present with nocturnal nonepileptic paroxysmal events may include not only sleep-related disorders per se but also psychiatric/behavioral conditions"benign" paroxysmal phenomena with unrelated etiology, and nonneurologic disorders. These phenomena, especially when involving complex motor activity, such as that observed in parasomnias, nocturnal panic attacks, and rapid eye movement behavior disorders may be difficult to differentiate from seizures. Moreover, there is increasing awareness that certain sleep disorders, such as sleep-disordered breathing, may coexist with epilepsy. There are several clinical and electrographical features that allow an accurate diagnosis, and diagnostic tools such as video-EEG polysomnography may be essential.